Lee,
I'm a bit confused here, and I suspect you are, scales are for measuring the amount of powder, a dropper is for adding powder which means they have to be used in conjunction with each other.
Now are you talking about using a powder measure and "Throwing" the powder directly into the case, as opposed to measuring each separate charge individually. If so then IMHO if you have a powder dispenser set up and you are making hunting rounds, then I would go with the dispenser and check the weight being thrown by measuring every tenth charge.
John